Lipid Profile Assessment

Patient Evaluation and Testing

Fasting for at least 12 hours is required when initial non-fasting triglycerides are ≥400 mg/dL, as recommended by the European Society of Cardiology 1
Lipid profiles should be obtained at least once every 5 years in adults age ≥20 years, with more frequent measurements for persons with multiple risk factors, according to the American College of Cardiology 2
Total cholesterol and HDL levels can be measured on non-fasting samples, as stated by the American Academy of Family Physicians 3
Abnormal results should be confirmed by a repeated sample on a separate occasion, as recommended by the American Academy of Family Physicians 3
Total cholesterol levels can be measured at any time of day in non-fasting patients because levels of total cholesterol do not vary appreciably with eating 4

Direct LDL-C measurement is recommended when triglycerides are ≥400 mg/dL or LDL-C levels are very low (<70 mg/dL), as noted by the European Society of Cardiology and supported by 5, 6, 7, 1
The Friedewald formula (LDL-C = Total Cholesterol - HDL-C - (Triglycerides/5)) can be used to calculate LDL-C when triglycerides are less than a certain threshold, but becomes progressively less accurate as triglyceride levels increase, according to the American College of Cardiology 2, 6
The Martin-Hopkins method can be used as an alternative to the Friedewald formula, especially when triglycerides are between 150-399 mg/dL, and is valid in the non-fasting state 6

Lipid screening is recommended for children and adolescents with a family history of early cardiovascular disease or significant hypercholesterolemia, starting as early as age 2 years, with either fasting or non-fasting lipid profiles, according to the American College of Cardiology 8
Non-fasting non-HDL-C measurement is suggested for children and adolescents without cardiovascular risk factors, between ages 9-11 and again between 17-21 years, as recommended by the American College of Cardiology 8

Non-fasting lipid profiles are recommended for most routine clinical scenarios and are equally effective for cardiovascular risk assessment, according to the American Heart Association and American College of Cardiology 9, 6, 7
Non-fasting triglyceride levels are a superior predictor of cardiovascular disease risk compared with fasting levels, as they better reflect the body's typical metabolic state, according to the American Heart Association 9

Fasting lipid profiles are specifically indicated when initial non-fasting triglycerides are ≥400 mg/dL, evaluating patients with family history of premature ASCVD or genetic hyperlipidemia, diagnosing metabolic syndrome, and assessing patients at risk for hypertriglyceridemia-induced pancreatitis, with a strength of evidence considered high 10, 8, 11, 6
Patients with diabetes should avoid prolonged fasting (>14 hours) to prevent hypoglycemia, especially if on insulin or sulfonylureas, and should consult healthcare providers about medication timing when fasting 12, 13, 14, 15, 16, 17, 18, 19

Non-HDL cholesterol (Total Cholesterol - HDL Cholesterol) can be used as an alternative marker, especially when triglycerides are elevated 5
Standardized blood sampling conditions are recommended, including having the patient seated for at least 5 minutes before blood draw, not applying the tourniquet for more than 1 minute before blood withdrawal, and consistency in using either serum or plasma tubes 9
The following table shows the maximum change in lipid measurements:

Initial follow-up (4-8 weeks after starting therapy) with a fasting lipid profile is recommended, and long-term stable therapy with non-fasting lipid profile is acceptable, according to the American College of Cardiology 10, 8, 6